Characteristics of optical waveguide type glucose sensor

A simple biosensor using three-layer slab optical waveguide has been developed to measure the biomolecular concentration. The purpose of this study is to evaluate the characteristics of optical waveguide sensor. Sensing objects are glucose solution and dye solution. The optical source is an Ar laser (λ=488 nm). Because the absorption peaks of the red colored glucose solution using GOD-POD method is near the 500 nm. A sample was dropped onto the sample layer the sensing characteristics which are the dependence of glucose concentration and the dependence of interaction length were evaluated. By using a tapered waveguide, the longest penetration of evanescent wave was investigated and the optimized guiding layer thickness for high sensitivity was discussed. The developed sensor has been applied to measure wide ranging glucose concentration